The role of sex, training load, and sports type in athletic cardiac remodelling: Insights from T1 and T2 mapping via cardiac magnetic resonance

BACKGROUND

Cardiovascular magnetic resonance (CMR) imaging, utilising native T1 and T2 mapping, provides a non-invasive method for assessing myocardial tissue properties, contributing to the clinical evaluation of the athlete's heart.

OBJECTIVE

To evaluate T1 and T2 mapping alterations and their association with sex, training volume, sports type, and other standard CMR parameters of the athlete's heart.

METHODS

We conducted a cross-sectional analysis of healthy elite athletes (≥10 training hours/week) and sedentary controls (≤5 h/week) who underwent detailed cardiology screening. CMR was performed, and native T1 and T2 values were quantified.

RESULTS

Of the 199 healthy participants (115 elite athletes, 24 ± 5 years, 70 % males; 84 sedentary volunteers, 26 ± 3 years, 58 % males), athletes had higher ventricular volumes, left ventricular mass (LVMi), and lower ejection fractions than volunteers. Athletes showed lower T1 values (male athletes:941 ± 23 ms vs. 960 ± 21 ms, p < 0.01; female athletes:970 ± 20 ms vs. 982 ± 25 ms, p < 0.01). T1 negatively correlated with training hours and LVMi (Rho: -0.554, p < 0.001). T1 values were positively associated with female sex with 22 ms (CI 14.3, 29.7, p < 0.001) higher values than males, while each additional hour in weekly exercise volume was associated with a 0.5 ms (CI -0.84, -0.11, p = 0.011) decrease. Compared to strength and mixed athletes, endurance athletes showed more pronounced myocardial adaptation, reflected in lower T1.

CONCLUSION

Sex, training volume, and type of sport significantly influence CMR-derived T1 and T2 values. This study highlights the critical need for sex- and sport-type-specific reference ranges in assessing myocardial remodelling in athletes, facilitating the distinction between benign athletic remodelling and (early) pathological changes.

Gender-affirming hormone therapy and its impact on myocardial mass and cardiac function: a prospective magnetic resonance cohort study on transgender men and women

OBJECTIVE

Differences in cardiac parameters such as myocardial mass, left ventricular ejection fraction (LVEF), cardiac output, and brain natriuretic peptide (NT-proBNP) levels between cisgender men and women are well established. No evidence exists regarding changes in myocardial mass or cardiac function parameters in transgender individuals undergoing gender-affirming hormone therapy (GAHT).

DESIGN, SETTING, PARTICIPANTS, AND MAIN OUTCOMES

A prospective study enrolling transgender individuals under GAHT (20 individuals assigned female at birth [AFAB] and 15 assigned male at birth [AMAB]) was conducted at the Medical University of Vienna from 2019 to 2022. A 3-Tesla electrocardiogram-gated magnetic resonance imaging measured myocardial mass, LVEF, and other cardiac function parameters before GAHT and at 6-month follow-up. Myocardial lipid content was quantified using magnetic resonance spectroscopy.

RESULTS

In AFAB, myocardial mass increased significantly after 6 months of GAHT from mean (±SD) 48 (±8) g/m2 at baseline to 54 (±7) g/m2 at follow-up (P = .011). Individuals assigned male at birth showed a nonsignificant decrease of 4 (±14) g/m2 in myocardial mass. In both groups, no significant changes were noted in LVEF, stroke volume, cardiac output, or peak filling rate. Neither testosterone (AFAB: r = -0.127, P = .679; AMAB: r = -0.127, P = .679) nor estradiol levels (AFAB: r = -0.154, P = .616; AMAB: r = -0.154, P = .616) nor body mass index was related to myocardial mass at follow-up. Brain natriuretic peptide levels in AFAB were significantly reduced at follow-up (from median [IQR] 41 [26-57] to 19 [12-34] pg/mL).

CONCLUSIONS

Myocardial mass increased, while NT-proBNP levels decreased significantly in AFAB after 6 months of GAHT. However, no significant changes in cardiac function were noted in AMAB and AFAB.

REGISTRATION

ClinicalTrials.gov: NCT06245681 (registered 07 February 2024, https://classic.clinicaltrials.gov/ct2/show/NCT06245681).

Multimodality imaging in arrhythmogenic cardiomyopathy - From diagnosis to management

Arrhythmogenic Cardiomyopathy (AC), an inherited cardiac disorder characterized by myocardial fibrofatty replacement, carries a significant risk of sudden cardiac death (SCD) due to ventricular arrhythmias. A comprehensive multimodality imaging approach, including echocardiography, cardiac magnetic resonance imaging (CMR), and cardiac computed tomography (CCT), allows for accurate diagnosis, effective risk stratification, vigilant monitoring, and appropriate intervention, leading to improved patient outcomes and the prevention of SCD. Echocardiography is primary tool ventricular morphology and function assessment, CMR provides detailed visualization, CCT is essential in early stages for excluding congenital anomalies and coronary artery disease. Echocardiography is preferred for follow-up, with CMR capturing changes over time. The strategic use of these imaging methods aids in confirming AC, differentiating it from other conditions, tracking its progression, managing complications, and addressing end-stage scenarios.

Electrocardiographic manifestations in female team handball players: analyzing ECG changes in athletes

Introduction

Long-term intense training leads to structural, functional, and electrical remodeling of the heart. How different sports affect the heart has not been fully investigated, particularly for female athletes. The aim of the present study was to investigate the morphology of 12-lead resting electrocardiogram (ECG) in elite female handball players compared to non-athlete female subjects. Potential changes will be explored to see if they could be explained by differences in cardiac dimensions and exercise hours.

Materials and methods

A cross-sectional study of 33 elite female team handball players compared to 33 sex and age-matched, non-athletic controls (age range 18-26 years) was performed. All participants underwent a resting 12-lead ECG and an echocardiographic examination. ECG variables for left ventricular hypertrophy and durations were evaluated and adjusted for cardiac dimensions and exercise hours using ANCOVA analysis. A linear regression analysis was used to describe relation between echocardiographic and ECG measures and exercise hours.

Results

The female handball players had larger cardiac dimensions and significantly lower heart rate and QTc duration (Bazett's formula) as well as increased QRS and QT durations compared to controls. The 12-lead sum of voltage and the 12-lead sum of voltage ∗ QRS were significantly higher among handball players. Changes in ECG variables reflecting the left ventricle could in part be explained by left ventricular size and exercise hours. Correlation with exercise hours were moderately strong in most of the echocardiographic measures reflecting left ventricular (LV), left ventricular mass (LVM), left atrium (LA) and right atrium (RA) size. Poor to fair correlations were seen in the majority of ECG measures.

Conclusions

Female team handball players had altered ECGs, longer QRS and QT durations, higher 12-lead sum of voltage and 12-lead sum of voltage ∗ QRS as well as shorter QTc (Bazett's formula) duration compared to non-athletic controls. These findings could only partly be explained by differences in left ventricular size. Despite larger atrial size in the athletes, no differences in P-wave amplitude and duration were found on ECG. This suggest that both structural, and to some degree electrical remodeling, occur in the female team handball players' heart and highlight that a normal ECG does not rule out structural adaptations. The present study adds knowledge to the field of sports cardiology regarding how the heart in female team handball players adapts to this type of sport.

Routine first-trimester pre-eclampsia screening and maternal left ventricular geometry

OBJECTIVE

Pre-eclampsia (PE) is a pregnancy complication associated with premature cardiovascular disease morbidity and mortality (i.e. before 60 years of age or in the first year postpartum). PE is associated with adverse left ventricular (LV) remodeling in the peri- and postpartum periods, an independent risk factor for cardiovascular disease. This study aimed to compare LV geometry by LV mass (LVM) and LVM index (LVMI) between participants with a high vs low screening risk for preterm PE in the first trimester.

METHODS

This was a prospective cohort study of singleton pregnancies between 11 + 0 and 13 + 6 weeks' gestation that underwent screening for preterm PE as part of their routine first-trimester ultrasound assessment at a tertiary center in London, UK, from February 2019 until March 2020. Screening for preterm PE was performed using the Fetal Medicine Foundation algorithm. Participants with a screening risk of ≥ 1 in 50 for preterm PE were classified as high risk and those with a screening risk of ≤ 1 in 500 were classified as low risk. All participants underwent two-dimensional and M-mode transthoracic echocardiography.

RESULTS

A total of 128 participants in the first trimester of pregnancy were included in the analysis, with 57 (44.5%) participants screened as low risk and 71 (55.5%) participants as high risk for PE. The risk groups did not vary in maternal age and gestational age at assessment. Maternal body surface area and body mass index were significantly higher in the high-risk group (all P < 0.05). The high-risk participants were significantly more likely to be Afro-Caribbean, nulliparous and have a family history of hypertensive disease in pregnancy as well as other cardiovascular disease (all P < 0.05). In addition, mean arterial blood pressure (P < 0.001), mean heart rate (P < 0.001), median LVM (130.06 (interquartile range, 113.62-150.50) g vs 97.44 (81.68-114.16) g; P < 0.001) and mean LVMI (72.87 ± 12.2 g/m2 vs 57.54 ± 12.72 g/m2 ; P < 0.001) were significantly higher in the high-risk group. Consequently, those in the high-risk group were more likely to have abnormal LV geometry (37.1% vs 7.0%; P < 0.001).

CONCLUSIONS

Early echocardiographic assessment in participants at high risk of preterm PE may unmask clinically healthy individuals who are at increased risk for future cardiovascular disease. Adverse cardiac remodeling in the first trimester of pregnancy may be an indicator of decreased cardiovascular reserve and subsequent dysfunctional cardiovascular adaptation in pregnancy. © 2023 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Normative values of non-invasively assessed RV function and pulmonary circulation coupling for pre-participation screening derived from 497 male elite athletes

BACKGROUND

Reference values for right ventricular function and pulmonary circulation coupling were recently established for the general population. However, normative values for elite athletes are missing, even though exercise-related right ventricular enlargement is frequent in competitive athletes.

METHODS

We examined 497 healthy male elite athletes (age 26.1 ± 5.2 years) of mixed sports with a standardized transthoracic echocardiographic examination. Tricuspid annular plane excursion (TAPSE) and systolic pulmonary artery pressure (SPAP) were measured. Pulmonary circulation coupling was calculated as TAPSE/SPAP ratio. Two age groups were defined (18-29 years and 30-39 years) and associations of clinical parameters with the TAPSE/SPAP ratio were determined and compared for each group.

RESULTS

Athletes aged 18-29 (n = 349, 23.8 ± 3.5 years) displayed a significantly lower TAPSE/SPAP ratio (1.23 ± 0.3 vs. 1.31 ± 0.33 mm/mmHg, p = 0.039), TAPSE/SPAP to body surface area (BSA) ratio (0.56 ± 0.14 vs. 0.6 ± 0.16 mm*m2/mmHg, p = 0.017), diastolic blood pressure (75.6 ± 7.9 vs. 78.8 ± 10.7 mmHg, p < 0.001), septal wall thickness (10.2 ± 1.1 vs. 10.7 ± 1.1 mm, p = 0.013) and left atrial volume index (27.5 ± 4.5 vs. 30.8 ± 4.1 ml/m2, p < 0.001), but a higher SPAP (24.2 ± 4.5 vs. 23.2 ± 4.4 mmHg, p = 0.035) compared to athletes aged 30-39 (n = 148, 33.1 ± 3.4 years). TAPSE was not different between the age groups. The TAPSE/SPAP ratio was positively correlated with left ventricular stroke volume (r = 0.133, p = 0.018) and training amount per week (r = 0.154, p = 0.001) and negatively correlated with E/E' lat. (r = -0.152, p = 0.005).

CONCLUSION

The reference values for pulmonary circulation coupling determined in this study could be used to interpret and distinguish physiological from pathological cardiac remodeling in male elite athletes.

Reduced myocardial strain of interventricular septum among male amateur marathon runners: a cardiac magnetic resonance study

OBJECTIVES

To analyze the long-term effect of multiple marathons on cardiac structure and function in amateur marathon runners compared with healthy controls.

DESIGN

Cross-sectional study using male amateur marathon runners (n = 32) and age-matched cohort of male healthy controls (n = 12).

METHODS

A total of 32 male amateur marathon runners (age 44 ± 7 years) and 12 male healthy controls (age 42 ± 8 years) underwent cardiac magnetic resonance (CMR). The relevant parameters of cardiac structure and function were studied employing feature-tracking strain analysis.

RESULTS

Amateur marathon runners showed lower heart rates, body mass index and body surface area. The left ventricular (LV) mass index, LV end-diastolic volume index and right ventricular end-systolic volume index were significantly higher in amateur marathon runners compared with healthy controls. Furthermore, walls of interventricular septum (IVS) in amateur marathon runners were thicker than healthy controls. There was no significant difference between two groups in the global myocardial strain (MS) in LV. However, the segmental radial and circumferential strains of the LV were lower in amateur marathon runners compared to healthy controls, specifically in the 8th and 9th segments. Finally, we also found as the total running intensity increased, so did global longitudinal strain.

CONCLUSIONS

We reported higher wall thickness and lower regional radial and circumferential strain in the IVS region in amateur marathon runners, suggesting that prolonged and high-intensity exercise may cause cardiac remodeling. Further studies are needed to investigate whether this is an adaptive or maladaptive change in amateur marathon runners.

Evolving spectrum of arrhythmogenic cardiomyopathy: Implications for Sports Cardiology

Arrhythmogenic cardiomyopathy (ACM) is a genetic heart muscle disease, structurally characterized by progressive fibro-fatty replacement of the normal myocardium and clinically by ventricular arrhythmias (VAs). Predominantly thanks to the use of cardiac magnetic resonance, we have learnt that the spectrum of the disease encompasses not only the classical right ventricular phenotype, but also biventricular and left dominant variants. Sport activity contributes to the phenotypic expression and progression of ACM and may trigger life-threatening VAs and sudden cardiac death (SCD). We conducted a review of the literature about ACM and its implications in Sport Cardiology and summarized the main findings in this topic. Early identification of affected athletes through preparticipation screening (PPS) is fundamental but, while classical right-ventricular or biventricular phenotypes are usually suspected because of electrocardiogram (ECG) and echocardiographic abnormalities, variants with predominant left ventricular involvement are often characterized by normal ECG and unremarkable echocardiography. Usually the only manifestations of such variants are exercise-induced VAs and for this reason exercise testing may empower the diagnostic yield of the PPS. Patients with ACM are not eligible to competitive sports activity, but low-to-moderate intensity physical activity under medical supervision is possible in most cases.

Different methods, different results? Threshold-based versus conventional contouring techniques in clinical practice

BACKGROUND

The quantitative differences of left and right ventricular (LV, RV) parameters of using different cardiac MRI (CMR) post-processing techniques and their clinical impact are less studied. We aimed to assess the differences and their clinical impact between the conventional contouring (CC) and the threshold-based (TB) methods using 70% and 50% thresholds in different hypertrabeculated conditions.

METHODS

This retrospective study included 30 dilated cardiomyopathy, 30 left ventricular non-compaction (LVNC), 30 arrhythmogenic cardiomyopathy patients, 30 healthy athletes and 30 healthy volunteers. All participants underwent CMR imaging on 1.5 T. Cine sequences were used to derive measures of the cardiac volumes, function, total muscle mass (TMi) and trabeculae and papillary muscle mass (TPMi) using CC and TB segmentation methods.

RESULTS

Comparing the CC and the 70% and 50% threshold TB methods, the LV and RV volumes were significantly lower, the ejection fraction (EF) and the TMi were significantly higher with the TB methods. Between the two threshold setups, only TPMi was significantly higher with the 70% threshold. Regarding the clinical benefits, the LVNC was the only group in whom all the diagnostic and therapeutic decisions and risk stratification were influenced using the TB method. Diagnostic changes occurred in three-quarters of the population, and all the cardiomyopathy groups were affected regarding the decision-making about pharmaco- and device therapy.

CONCLUSIONS

Using the TB method, only TPMi was significantly higher with the 70% threshold than the 50% setup, and both of them differed significantly from the CC technique, with relevant clinical impacts in all patient groups.

Relating QRS voltages to left ventricular mass and body composition in elite endurance athletes

PURPOSE

Electrocardiogram (ECG) QRS voltages correlate poorly with left ventricular mass (LVM). Body composition explains some of the QRS voltage variability. The relation between QRS voltages, LVM and body composition in endurance athletes is unknown.

METHODS

Elite endurance athletes from the Pro@Heart trial were evaluated with 12-lead ECG for Cornell and Sokolow-Lyon voltage and product. Cardiac magnetic resonance imaging assessed LVM. Dual energy x-ray absorptiometry assessed fat mass (FM) and lean mass of the trunk and whole body (LBM). The determinants of QRS voltages and LVM were identified by multivariable linear regression. Models combining ECG, demographics, DEXA and exercise capacity to predict LVM were developed.

RESULTS

In 122 athletes (19 years, 71.3% male) LVM was a determinant of the Sokolow-Lyon voltage and product (β = 0.334 and 0.477, p < 0.001) but not of the Cornell criteria. FM of the trunk (β = - 0.186 and - 0.180, p < 0.05) negatively influenced the Cornell voltage and product but not the Sokolow-Lyon criteria. DEXA marginally improved the prediction of LVM by ECG (r = 0.773 vs 0.510, p < 0.001; RMSE = 18.9 ± 13.8 vs 25.5 ± 18.7 g, p > 0.05) with LBM as the strongest predictor (β = 0.664, p < 0.001). DEXA did not improve the prediction of LVM by ECG and demographics combined and LVM was best predicted by including VO₂max (r = 0.845, RMSE = 15.9 ± 11.6 g).

CONCLUSION

LVM correlates poorly with QRS voltages with adipose tissue as a minor determinant in elite endurance athletes. LBM is the strongest single predictor of LVM but only marginally improves LVM prediction beyond ECG variables. In endurance athletes, LVM is best predicted by combining ECG, demographics and VO₂max.

Reference ventricular dimensions and function parameters by cardiovascular magnetic resonance in highly trained Caucasian athletes

BACKGROUND

Data regarding cardiovascular magnetic resonance (CMR) reference values in athletes have not been well determined yet. Using CMR normal reference values derived from the general population may be misleading in athletes and may have clinical implications.

AIMS

To determine reference ventricular dimensions and function parameters and ratios by CMR in high performance athletes.

METHODS

Elite athletes and age- and gender-matched sedentary healthy controls were included. Anatomical and functional variables, including biventricular volumes, mass, systolic function, wall thickness, sphericity index and longitudinal function were determined by CMR.

RESULTS

A total of 148 athletes (29.2 ± 9.1 years; 64.8% men) and 124 controls (32.1 ± 10.5 years; 67.7% men) were included. Left ventricular (LV) mass excluding papillary muscles was 67 ± 13 g/m2 in the control group and increased from 65 ± 14 g/m2 in the low intensity sport category to 83 ± 16 g/m2 in the high cardiovascular demand sport category; P < 0.001. Regarding right ventricular (RV) mass, the data were 20 ± 5, 31 ± 6, and 38 ± 8 g/m2, respectively; P < 0.001. LV and RV volumes, and wall thickness were higher in athletes than in the control group, and also increased with sport category. However, LV and RV ejection fractions were similar in both groups. LV and RV dimensions, wall thickness and LV/RV ratios reference parameters for athletes are provided.

CONCLUSIONS

LV and RV masses, volumes, and wall thicknesses are higher in athletes than in sedentary subjects. Specific CMR reference ranges for athletes are provided and can be used as reference levels, rather than the standard upper limits used for the general population to exclude cardiomyopathy.

Assessment of hepatic fat content and prediction of myocardial fibrosis in athletes by using proton density fat fraction sequence

PURPOSE

To explore the characteristics of the hepatic fat content in athletes, and predict late gadolinium enhancement (LGE) based on magnetic resonance imaging-proton density fat fraction (MRI-PDFF).

MATERIAL AND METHODS

From March 2020 to March 2021, 233 amateur athletes and 42 healthy sedentary controls were prospectively recruited. The liver fat content of four regions of interest (ROIs 1-4), the mean liver fat fraction (FF), cardiac function, and myocardium LGE were recorded, respectively. The values of ROIs 1-4 and FF were compared between athletes and controls. According to the liver fat content threshold for distinguishing athletes and controls, the cutoff total exercise time that induced a change in liver fat was obtained. The correlations among the liver fat content, cardiac function, and other parameters were analyzed. Moreover, the liver fat content was used to predict myocardium LGE by logistic regression.

RESULTS

There were significant differences for the values of ROI 1, ROI 3, ROI 4, and FF between athletes and controls (allp< 0.05). The cutoff total exercise time for inducing a change in the liver fat content was 1680 h (area under the curve [AUC] = 0.593, specificity = 83.3,p< 0.05). Blood indexes, cardiac function, and basic clinical parameters were related to liver fat content (allp< 0.05). The prediction model for LGE had an AUC value of 0.829 for the receiver operator characteristic curve.

CONCLUSION

MRI-PDFF could assess liver fat content and predict cardiac fibrosis in athletes for risk stratification and follow-up.

Certainties and Uncertainties of Cardiac Magnetic Resonance Imaging in Athletes

Prolonged and intensive exercise induces remodeling of all four cardiac chambers, a physiological process which is coined as the “athlete’s heart”. This cardiac adaptation, however, shows overlapping features with non-ischemic cardiomyopathies, such as dilated, arrhythmogenic and hypertrophic cardiomyopathy, also associated with athlete’s sudden cardiac death. Cardiac magnetic resonance (CMR) is a well-suited, highly reproducible imaging modality that can help differentiate athlete’s heart from cardiomyopathy. CMR allows accurate characterization of the morphology and function of cardiac chambers, providing full coverage of the ventricles. Moreover, it permits an in-depth understanding of the myocardial changes through specific techniques such as mapping or late gadolinium enhancement. In this narrative review, we will focus on the certainties and uncertainties of the role of CMR in sports cardiology. The main aspects of physiological adaptation due to regular and intensive sports activity and the application of CMR in highly trained athletes will be summarized.

Is cardiac involvement prevalent in highly trained athletes after SARS-CoV-2 infection? A cardiac magnetic resonance study using sex-matched and age-matched controls

OBJECTIVES

To investigate the cardiovascular consequences of SARS-CoV-2 infection in highly trained, otherwise healthy athletes using cardiac magnetic resonance (CMR) imaging and to compare our results with sex-matched and age-matched athletes and less active controls.

METHODS

SARS-CoV-2 infection was diagnosed by PCR on swab tests or serum immunoglobulin G antibody tests prior to a comprehensive CMR examination. The CMR protocol contained sequences to assess structural, functional and tissue-specific data.

RESULTS

One hundred forty-seven athletes (94 male, median 23, IQR 20-28 years) after SARS-CoV-2 infection were included. Overall, 4.7% (n=7) of the athletes had alterations in their CMR as follows: late gadolinium enhancement (LGE) showing a non-ischaemic pattern with or without T2 elevation (n=3), slightly elevated native T1 values with or without elevated T2 values without pathological LGE (n=3) and pericardial involvement (n=1). Only two (1.4%) athletes presented with definite signs of myocarditis. We found pronounced sport adaptation in both athletes after SARS-CoV-2 infection and athlete controls. There was no difference between CMR parameters, including native T1 and T2 mapping, between athletes after SARS-CoV-2 infection and the matched athletic groups. Comparing athletes with different symptom severities showed that athletes with moderate symptoms had slightly greater T1 values than athletes with asymptomatic and mildly symptomatic infections (p<0.05). However, T1 mapping values remained below the cut-off point for most patients.

CONCLUSION

Among 147 highly trained athletes after SARS-CoV-2 infection, cardiac involvement on CMR showed a modest frequency (4.7%), with definite signs of myocarditis present in only 1.4%. Comparing athletes after SARS-CoV-2 infection and healthy sex-matched and age-matched athletes showed no difference between CMR parameters, including native T1 and T2 values.

Cardiodiagnostic sex-specific differences of the female athlete in sports cardiology

The cardiovascular care of highly active individuals and competitive athletes has developed into an important focus within the field of sports medicine. An evolving understanding of exercise-induced cardiovascular remodeling in athletes has led to a more robust characterization of physiologic adaptation versus pathological dysfunction, but this distinction is often challenging due to diagnostic commonalities. Current data reflects sporting-focused analyses of mainly male athletes, which may not be easily applicable to the female athletic heart. Increasingly female-specific cardiac dimensional and physiologic data are starting to emerge from comparative studies that may be utilized to address this growing need, and further guide individualized care. Here, we review current literature evaluating female-specific cardiovascular adaptations of the athletic heart, and formulate a discussion on cardiac remodeling, cardiodiagnostic findings, etiologic mechanisms, limitations of currently available data, and direction for future research in the cardiovascular care of female athletes.

Rationale and design of the PROspective ATHletic Heart (Pro@Heart) study: long-term assessment of the determinants of cardiac remodelling and its clinical consequences in endurance athletes

Background

Exercise-induced cardiac remodelling (EICR) results from the structural, functional and electrical adaptations to exercise. Despite similar sports participation, EICR varies and some athletes develop phenotypic features that overlap with cardiomyopathies. Training load and genotype may explain some of the variation; however, exercise ‘dose’ has lacked rigorous quantification. Few have investigated the association between EICR and genotype.

Objectives

(1) To identify the impact of training load and genotype on the variance of EICR in elite endurance athletes and (2) determine how EICR and its determinants are associated with physical performance, health benefits and cardiac pathology.

Methods

The Pro@Heart study is a multicentre prospective cohort trial. Three hundred elite endurance athletes aged 14–23 years will have comprehensive cardiovascular phenotyping using echocardiography, cardiac MRI, 12-lead ECG, exercise-ECG and 24-hour-Holter monitoring. Genotype will be determined using a custom cardiomyopathy gene panel and high-density single-nucleotide polymorphism arrays. Follow-up will include online tracking of training load. Cardiac phenotyping will be repeated at 2, 5, 10 and 20 years.

Results

The primary endpoint of the Pro@Heart study is the association of EICR with both training load and genotype. The latter will include rare variants in cardiomyopathy-associated genes and polygenic risk scores for cardiovascular traits. Secondary endpoints are the incidence of atrial and ventricular arrhythmias, physical performance and health benefits and their association with training load and genotype.

Conclusion

The Pro@Heart study is the first long-term cohort study to assess the impact of training load and genotype on EICR.

Trial registration number

NCT05164328; ACTRN12618000716268.

Sex Matters: A Comprehensive Comparison of Female and Male Hearts

Cardiovascular disease in women remains under-diagnosed and under-treated. Recent studies suggest that this is caused, at least in part, by the lack of sex-specific diagnostic criteria. While it is widely recognized that the female heart is smaller than the male heart, it has long been ignored that it also has a different microstructural architecture. This has severe implications on a multitude of cardiac parameters. Here, we systematically review and compare geometric, functional, and structural parameters of female and male hearts, both in the healthy population and in athletes. Our study finds that, compared to the male heart, the female heart has a larger ejection fraction and beats at a faster rate but generates a smaller cardiac output. It has a lower blood pressure but produces universally larger contractile strains. Critically, allometric scaling, e.g., by lean body mass, reduces but does not completely eliminate the sex differences between female and male hearts. Our results suggest that the sex differences in cardiac form and function are too complex to be ignored: the female heart is not just a small version of the male heart. When using similar diagnostic criteria for female and male hearts, cardiac disease in women is frequently overlooked by routine exams, and it is diagnosed later and with more severe symptoms than in men. Clearly, there is an urgent need to better understand the female heart and design sex-specific diagnostic criteria that will allow us to diagnose cardiac disease in women equally as early, robustly, and reliably as in men.

Systematic Review Registration

https://livingmatter.stanford.edu/.

Exercise and the Female Heart

Female participation in sport has increased sharply during the last few decades, and for the third straight Olympic Games, there were more women than men on the US roster for the 2020 Tokyo Games. Given this, an understanding of the differences between men and women with respect to exercise-induced cardiac remodeling is critical for those caring for female athletes. Recent studies have provided insight into female-specific cardiac remodeling and have enhanced our understanding on the upper limits of cardiac remodeling in female athletes and how these adaptations compare with sedentary females, male athletes, and cardiomyopathies. Female athletes display fewer signs of adaptive remodeling on ECG compared with male athletes. Structurally, male athletes have larger absolute cardiac dimensions, but female athletes have similar or larger chamber size when adjusted for body size. Female athletes have a lower incidence of sudden cardiac arrest or death compared with male athletes in the early competitive years (high school, college, and professional) and in the masters athlete years. In addition, female athletes are less likely to have coronary disease and atrial fibrillation compared with male athletes. Data on longevity indicate that female athletes live longer than their sedentary counterparts. Unlike men, there has been no convincing association of extreme exercise and cardiovascular disease in longer-term endurance female athletes. The underlying mechanisms of these sex-based differences are not very well understood, and future studies are warranted to better understand the mechanisms of cardiac adaptation in female athletes.

Talent Development in Young Cross-Country Skiers: Longitudinal Analysis of Anthropometric and Physiological Characteristics

Introduction: Very little is known about talent development and selection processes in young cross-country skiers.

Aim: (1) to analyze the effect of age on anthropometric and physiological parameters in medium-to-high level cross-country skiers during the late teenage period; (2) to describe parameters' trend in selected talents after the late teenage period; (3) to define which characteristics during the late teenage period could discriminate against further talent selection.

Method: We found 14 male (M) and nine (F) athletes in our database, identified as talents by regional teams during the late teenage period, who performed the same diagonal-stride roller-skiing incremental test to exhaustion at 17 and 18 years old. Of these, four M and three F teenagers performed four further evaluations, and were selected by the national team. Age effect during the late teenage period was verified on anthropometric and physiological parameters measured at maximal intensity (MAX), first (VT1), and second (VT2) ventilatory thresholds, and 3° and 6° of treadmill incline. An observational analysis allowed to evaluate parameters' trend after the late teenage period in selected athletes, and to determine possible characteristics early discriminating further selection.

Results: During the late teenage period, height, weight, and BMI was still raising in M as well as V'O₂ at VT2 and 6° of treadmill incline (all P > 0.05). In F, mass-scaled V'O₂ MAX increased while heart rate (HR) at MAX and VT2 decreased (all P > 0.05). Since the late teenage period, all selected males showed maximal ventilation volumes, absolute V'O₂ at MAX, VT1, and VT2 that were within or above the 75th percentile of their group; the same was found in selected females for mass-scaled V'O₂ MAX, VT1, and VT2 time. After the late teenage period, all selected athletes showed an increasing trend for VT2 time, while a decreasing trend for sub-maximal energetic cost, %V'O₂ and HR.

Discussion: During the late teenage period, males are still completing their maturation process. Since the late teenage period, some physiological parameters seem good indicators to early discriminate for further talents. A progressive increase in skiing efficiency was demonstrated in developing talents of both sexes after the late teenage period.

Age matters: differences in exercise-induced cardiovascular remodelling in young and middle aged healthy sedentary individuals

AIMS

Remodelling of the cardiovascular system (including heart and vasculature) is a dynamic process influenced by multiple physiological and pathological factors. We sought to understand whether remodelling in response to a stimulus, exercise training, altered with healthy ageing.

METHODS

A total of 237 untrained healthy male and female subjects volunteering for their first time marathon were recruited. At baseline and after 6 months of unsupervised training, race completers underwent tests including 1.5T cardiac magnetic resonance, brachial and non-invasive central blood pressure assessment. For analysis, runners were divided by age into under or over 35 years (U35, O35).

RESULTS

Injury and completion rates were similar among the groups; 138 runners (U35: n = 71, women 49%; O35: n = 67, women 51%) completed the race. On average, U35 were faster by 37 minutes (12%). Training induced a small increase in left ventricular mass in both groups (3 g/m2, P < 0.001), but U35 also increased ventricular cavity sizes (left ventricular end-diastolic volume (EDV)i +3%; left ventricular end-systolic volume (ESV)i +8%; right ventricular end-diastolic volume (EDV)i +4%; right ventricular end-systolic volume (ESV)i +5%; P < 0.01 for all). Systemic aortic compliance fell in the whole sample by 7% (P = 0.020) and, especially in O35, also systemic vascular resistance (-4% in the whole sample, P = 0.04) and blood pressure (systolic/diastolic, whole sample: brachial -4/-3 mmHg, central -4/-2 mmHg, all P < 0.001; O35: brachial -6/-3 mmHg, central -6/-4 mmHg, all P < 0.001).

CONCLUSION

Medium-term, unsupervised physical training in healthy sedentary individuals induces measurable remodelling of both heart and vasculature. This amount is age dependent, with predominant cardiac remodelling when younger and predominantly vascular remodelling when older.